CVE-2023-46836 (GCVE-0-2023-46836)
Vulnerability from cvelistv5
Published
2024-01-05 16:34
Modified
2025-06-03 14:40
Severity ?
4.7 (Medium) - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
Summary
The fixes for XSA-422 (Branch Type Confusion) and XSA-434 (Speculative Return Stack Overflow) are not IRQ-safe. It was believed that the mitigations always operated in contexts with IRQs disabled. However, the original XSA-254 fix for Meltdown (XPTI) deliberately left interrupts enabled on two entry paths; one unconditionally, and one conditionally on whether XPTI was active. As BTC/SRSO and Meltdown affect different CPU vendors, the mitigations are not active together by default. Therefore, there is a race condition whereby a malicious PV guest can bypass BTC/SRSO protections and launch a BTC/SRSO attack against Xen.
References
security@xen.orghttps://xenbits.xenproject.org/xsa/advisory-446.htmlPatch, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://xenbits.xenproject.org/xsa/advisory-446.htmlPatch, Vendor Advisory
Impacted products
Vendor Product Version
Xen Xen Create a notification for this product.
Show details on NVD website

To clipboard 

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